Acoustic pulse-echo imaging tools are known in the art. The acoustic pulse-echo imaging tool usually comprises a rotating head on which is mounted a piezoelectric element transducer. The transducer periodically emits an acoustic energy pulse on command from a controller circuit in the tool. After emission of the acoustic energy pulse, the transducer can be connected to a receiving circuit, generally located in the tool, for measuring a returning echo of the previously emitted acoustic pulse which is reflected off the borehole wall. By processing the reflected signal, it is possible to infer something about the acoustic impedance characterizing the near-borehole environment. Specifically, changes in acoustic impedance are diagnostic of the geometry of the borehole.
Typically, as single acoustic pulse results in a plurality of reflections that may be received as a signal to be processed to estimate the arrival times and amplitudes with widely varying amplitudes and a highly reverberatory nature. The use of a single acoustic pulse and then waiting for a plurality of reflections requires considerable time and energy for evaluating the near-borehole environment. The present disclosure is directed towards apparatuses and methods for estimating parameters of the near-borehole environment using the arrival times and amplitudes of a plurality of reflections produced by a plurality of pulses, thus reducing the time and energy requirements.